Needleless access connector and method of use

ABSTRACT

A positive-displacement needleless access connector is disclosed that has a housing with a first luer fitting at a proximal end thereof, a base with a second luer fitting at a distal end thereof, and a valve element with a proximal end that creates a seal at the first luer fitting and fastens to the base so that a surface of the valve element is substantially flush with a surface of the base.

This application is a divisional application of application Ser. No.13/593,278, filed Aug. 23, 2012, entitled “NEEDLELESS ACCESS CONNECTORAND METHOD OF USE,” which is a divisional application Ser. No.12/730,961, filed Mar. 24, 2010, entitled “NEEDLELESS ACCESS CONNECTORAND METHOD OF USE,” both of which are hereby incorporated by referencein their entirety.

TECHNICAL FIELD

This disclosure relates to needleless access connectors and moreparticularly to positive displacement needleless access connectors.

BACKGROUND

Modern medical treatment often requires medical professionals tointroduce fluids into a patient or withdraw fluids from a patient. Forexample, a patient may need treatment that requires a medicalprofessional to withdraw urine or blood from the urethra or a vein,respectively. Conversely, the medical professional may need to introducedrugs or nutrients into the patient's vein (i.e., intravenously). Tocreate a path for the flow of fluid into or from the patient, one methodrequires that the medical practitioner use a catheter where one end ofthe catheter is inserted into the patient. The other end of the catheterconnects to an intravenous bag (IV bag), through an IV line. Needlelessaccess connectors employ valves that allow a medical practitioner toremove or add devices (e.g., IV bags) to the catheter without the use ofa needle. An example of a needleless access connector is shown in FIGS.1A and 1B.

FIG. 1A is a cut-away view of a current needleless access connector 100.Needleless access connector 100 includes housing 120, which has femaleluer fitting 101 at the proximal end, base 130, which has male luerfitting 102 at the distal end, and valve element 103, which sits insidehousing 120 and on top of base 130. Housing 120 and base 130 are madefrom rigid plastic, usually polycarbonate, and the valve element 103 ismade from liquid silicone so it is elastic and collapses. When in use,male luer fitting 102 is connected to, e.g., a catheter or to a femaleluer, and female luer fitting 101 is connected to a fluid reservoir,e.g., an IV bag or male luer. Female luer fitting 101 is connected tothe fluid reservoir via a second male luer fitting 106, which has ahollow member (as shown in FIG. 1B) and is inserted through the top offemale luer fitting 101. The insertion of male luer 106 collapses valveelement 103 down into volume 104 to break the seal and create a fluidflow path. FIG. 1B shows collapsible valve element 103 in the collapsedposition after insertion of male luer 106 into female luer 101. Maleluer 106 delivers fluid, e.g., from an IV bag, which flows around valveelement 103 into channels in male luer fitting 102 and into the catheteror female luer.

Inside valve element 103 is a gap (or septum, not shown), that is filledwith air. Needleless access connector 100 is a positive displacementdevice, so that when a new connection is made at female luer fitting101, device 100 pulls fluid in from the male side of the valve (i.e.,the side proximate male luer fitting 102). When a disconnection is madeat female luer fitting 101, device 100 pushes fluid in from the femaleside (i.e., the side proximate the top of female luer fitting 101). Theadvantage of positive displacement is that when a disconnection is made,device 100 expels fluid out of the male luer fitting 102 and effectivelyflushes the catheter. By contrast, some devices on the market today havenegative displacement, so that when a male luer (e.g., male luer 106) isdisconnected, such devices pull a small amount of liquid from the maleluer 102 side. When liquid is pulled from the male luer 102 side of acatheter that is attached to the vein of a patient, blood could bepulled into the catheter lumen and if this blood is left in the catheterlumen it may clot and cause health problems for the patient. Positivedisplacement connectors avoid this problem by pushing fluid out when amale luer (e.g., male luer 106) is disconnected from the needlelessaccess connector and its collapsible valve moves from its collapsedstate to its uncollapsed state. The purging of fluid, from positivedisplacement connectors, helps to prevent blood from entering the tip ofthe catheter, thereby preventing blood clotting/contamination and thus,bloodstream infections.

In operation, when the female end of needleless access connector 100 isaccessed by a male luer (FIG. 1B), valve element 103 is sufficientlyelastic so that it can bend out of the way to allow flow and then returnto its original shape after a disconnection is made at the female end.Thus, needleless access connector 100 re-seals itself and forms a flatsurface that can be disinfected at the top surface 110 using an alcoholswab.

Before needleless access connector 100 is used to connect a device to,for example, a catheter, needleless access connector 100 will containsome air. This air is removed before using needleless access connector100 with a catheter because otherwise it may be pumped into the patientcausing harm to the patient. Usually, to remove this air, the medicalpractitioner inverts the needleless access connector and attaches asyringe containing saline to the needleless access connector. The salineis then pushed through the needleless access connector, therebyexpelling the air from the connector. (This process is known as priming,and the minimum volume of liquid required to remove all the air from theneedleless access connector is known as the priming volume.) Somemedical practitioners prefer needleless access connectors with smallerpriming volumes to reduce delay in medication delivery.

After a needleless access connector is primed, the medical practitionerusually connects the male end 102 to a catheter (not shown) The medicalpractitioner connects a male luer from the IV bag (not shown) to theneedleless access connector. For example, a medical practitioner wouldconnect the end of syringe 106 to female luer fitting 101, as shown inFIG. 1B.

Of note in needleless access connector 100 is the shapes of housing 120,base 130, and valve element 103. Valve element 103 has flange 105, whichis a portion with an outer diameter greater than that of the body of thevalve element 103. Housing 120 has shoulder 107, which conforms toflange 105. When assembled, flange 105 is held securely between base 130and shoulder 107, thereby creating a seal between flange 105 and base130. The reason for the seal is so that the air in the septum can bevented out without the air getting into the fluid flow path from maleluer 106 to male luer 102. Although not shown herein, there are two ventholes in the y-axis direction that extend from the threaded portion ofbase 130 to the septum of valve element 103 that allow air out of andinto the septum as valve element 103 is compressed and uncompressedwithout mixing with the fluid. Once assembled, housing 120 and base 130are welded at interface 115.

Flange 105 increases the overall width of valve element 103, andconnector 100 allows the fluid to flow around flange 105, thereby makingconnector 100 itself wide. As a result, connector 100 can look big whencompared to a catheter (not shown) and especially when connector 100 isplaced against the skin of a neonate. Typical use of connector 100 is totape the catheter to a patient's skin near the point where the cathetercouples to connector 100. However, the wide shape of connector 100 maycause connector 100 to fit uncomfortably against the skin. Additionally,the width of connector 100 can make for a large priming volume.

BRIEF SUMMARY

Various embodiments include a connector with a valve element thatfastens to the base. For instance, in one embodiment, an example valveelement is flush with the base where the two components mate. In anotherexample, the base and the valve element couple to each other to createan assembly that has a greatest outer diameter that is smaller than aninner diameter of the housing.

Various embodiments minimize or eliminate the flange so that the widthprofile of the valve element, and the connector as a whole, can bereduced when compared to the prior solutions shown in FIGS. 1A and 1B.An example technique for eliminating the flange and fastening the valveelement to the base includes using a snap fitting that mates the valveelement to the base, though other embodiments can use other techniques.Additional embodiments include methods of manufacturing a connector.

The foregoing has outlined rather broadly the features and technicaladvantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter which form the subject of the claims of the invention. Itshould be appreciated by those skilled in the art that the conceptionand specific embodiment disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present invention. It should also be realized by thoseskilled in the art that such equivalent constructions do not depart fromthe spirit and scope of the invention as set forth in the appendedclaims. The novel features which are believed to be characteristic ofthe invention, both as to its organization and method of operation,together with further objects and advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. It is to be expressly understood, however, thateach of the figures is provided for the purpose of illustration anddescription only and is not intended as a definition of the limits ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, reference isnow made to the following descriptions taken in conjunction with theaccompanying drawings, in which:

FIG. 1A is a cut-away view of a current needleless access connector.FIG. 1B shows a collapsible valve element in the collapsed positionafter insertion of a male luer into a female luer.

FIGS. 2A and 2B provide an exploded illustration of an exemplarypositive displacement needleless access connector, adapted according toone embodiment of the invention.

FIGS. 3A and 3B provide an exploded illustration of the exemplarypositive displacement needleless access connector, adapted according toone embodiment of the invention.

FIG. 4 is a see-through illustration of the exemplary connector in use,according to one embodiment.

FIG. 5 is a cross-section illustration of the exemplary connector,adapted according to one embodiment, which is ninety degrees rotatedfrom the cross-sections of FIGS. 2A, B and 3A, B.

FIG. 6 is an illustration of the exemplary connector assembled and readyfor use, according to one embodiment.

FIG. 7 is an illustration of an exemplary connector, adapted accordingto one embodiment.

FIG. 8 is an illustration of an exemplary method for manufacturing apositive displacement needleless connector according to one embodiment.

DETAILED DESCRIPTION

FIGS. 2A and 2B provide an exploded illustration of exemplary positivedisplacement needleless access connector 200, adapted according to oneembodiment of the invention. FIG. 2A is a cut-away view, whereas FIG. 2Bshows the exterior of connector 200.

Connector 200 has three basic parts—base 210, valve element 220, andhousing 230. Housing 230 has female luer fitting 231 at the proximalend, which connects, for example, to a fluid reservoir, such as an IVbag. Base 210 and threads 232 form a male luer fitting at the distal endof connector 200, the male luer fitting connecting to, for example, acatheter that is in communication with a patient. Valve element 220includes septum 221, which is filled with air and vents to theatmosphere as it is compressed and uncompressed, as explained in moredetail below.

FIGS. 3A and 3B provide an exploded illustration of exemplary positivedisplacement needleless access connector 200, adapted according to oneembodiment of the invention. FIG. 3A is a cut-away view, whereas FIG. 3Bshows the exterior of connector 200, and both FIGS. 3A and 3B show base210 fastened to valve element 220.

Base 210 and valve element 220 are coupled together using, in thisembodiment, an interlocking male/female fitting 250, referred to hereinfor convenience as a snap fitting. The top of valve element 220 that isthe female part of the snap fitting 250 is made small enough so that ishas a tight, sealing squeeze at the corresponding portion of base 210that forms the male portion of snap fitting 250. In many embodiments,the seal at the snap fitting 250 is airtight, at least at normaloperating temperatures and pressures, in order to keep the air separatefrom the fluid in connector 200. During manufacturing, base 210 andvalve element 220 can be fastened together by forcing them together,either by hand or by machine. In some embodiments, about a pound offorce is sufficient to make the connection, and about two pounds issufficient to break the connection, though various embodiments maydiffer.

While FIGS. 3A and B show a snap fitting 250, the scope of embodimentsis not so limited. For instance, other embodiments may employ differenttypes of fastening fittings, such as threaded assemblies or otherfittings.

In the exemplary embodiment of FIGS. 3A and 3B, the outside surfaces ofbase 210 and valve element 220 are flush at snap fitting 250. Forreal-world devices it is understood that the outside surfaces of valveelement 220 and base 210 will rarely be exactly flush, but some amountof tolerance (e.g., about 2%) is acceptable in some embodiments. Thus,connector 200 replaces the flange of conventional positive displacementdevices (e.g., flange 105 of FIG. 1A) with the snap fitting 250 andflush outer surface shown in FIGS. 3A and 3B. The shape of valve element220, therefore, has a narrower profile, and can be used innarrower-profile connectors.

Base 210 and valve element 220 fasten together to form an assembly thatis placed into housing 230. Connector 200 uses a somewhat “v”-shapedfitting to mate base 210 to housing 230. Complementary surfaces 211 and233 are basically v-shaped but have slight curvature and fit together tohold base 210 in place when base 210 is inserted into housing 230. Asbase 210 is inserted, the complementary surfaces 211, 233 self-correctthe alignment of base 210 with respect to housing 230, acting like acam. Thus, if base 210 is inserted some arbitrary number of degrees outof alignment, complementary surfaces 211, 233 (once contacted) rotatebase 210 into place. As a result, base 210 sits precisely, and after theweld is made, air vents 212 will be able to vent to the atmosphere whiledistal flow channels 213 are connected to the male luer outlet of base210.

Distal flow channels 213 and air vents 212 are perpendicular to eachother in this embodiment. Thus, one of two air vents 212 is shown inFIG. 3B, whereas distal flow channels 213 are shown in cross-section inFIG. 3A. Flow and venting are shown in more detail in FIG. 4.

FIG. 4 is a see-through illustration of exemplary connector 200 in use,according to one embodiment. In FIG. 4, fluid is being transferred frommale luer connector 410, which is engaged with female luer fitting 231,through housing 230, through the male luer outlet of base 210 and intofemale luer fitting 402. Such an example may include transferring fluidfrom an IV bag {not shown) into a patient's bloodstream. While FIG. 4shows flow into a patient, it is understood that various embodiments ofthe invention also facilitate flow of fluids from a patient.

When there is no connection at the female luer fitting 231, valveelement 230 creates a seal at the proximal end of female luer fitting231 as well as at shoulder 234. Such seal prevents the flow of fluidsthrough connector 200 when not in use. Also, the seal at the proximalend of fitting 231 creates a flush surface that is swabbable. The sealsat the proximal end of female luer fitting 231 and at shoulder 234 areshown in FIG. 5.

During use, male luer fitting 401 collapses valve element 220 and breaksthe seals at shoulder 234 and at the proximal end of fitting 231. Fluidis then free to flow around valve element 230 and through housing 230via proximal flow channels 403, which are formed into the inner surfaceof housing 230. The weld at surfaces 211, 233 stops the fluid so thatthe fluid flows around the v-shape and into the distal flow channels213, where the fluid is directed out through the male luer outlet ofbase 210. Air from septum 221 is vented to the atmosphere through airvents 212 and into threaded chamber 404, which is part of the male luerfitting formed by base 210 and housing 230. The air passageway isdefined by vent 212 and the inner surface of housing 230, and the weldat surfaces 211, 233 creates a seal that keeps the air flow separatefrom the fluid flow. The threaded chamber 404 is not airtight, even whenengaged with female fitting 402, thereby allowing septum 221 tocommunicate with the ambient atmosphere as valve element 220 iscompressed, as in FIG. 4, or uncompressed.

FIG. 5 is a cross-section illustration of exemplary connector 200,adapted according to one embodiment, which is ninety degrees rotatedfrom the cross-sections of FIGS. 2A, B and 3A, B. Of note in FIG. 5 isthe air passageway from septum 221 to the atmosphere. The air passagewayincludes single vent 501, formed in base 210, and vents 212. The singlevent 501 and the vents 212 form a substantially “Y”-shaped airpassageway. This is in contrast to prior designs (not shown) thatinclude two or more separate vents, formed in the y-axis direction(“axially”), directly connecting the atmosphere to the septum.

During conventional manufacturing techniques, an injection moldingtechnique is used, and the two or more separate vents are created usinglong, thin pins inserted into the mold cavity when the material is hot.When the mold is opened, the long, thin pins are removed to form the twoor more separate vents. However, long, thin pins have a tendency tobreak during use. The general rule is that shorter and thicker pins lastlonger.

By contrast, base 210 has relatively wide and short vents 212 that canbe formed by correspondingly-shaped metal pieces in the mold. The airpassageway has a triangular broadening in each vent 212 from the centeraxis to the outer surface of base 210. The correspondingly-shaped metalpieces (not shown) are thicker and shorter than the long, thin pins ofconventional techniques and are, therefore, less subject to breakingSingle channel 501 is made relatively wide, and it is placed in theportion of base 210 that corresponds to the male portion of snap fitting250. Furthermore, since single channel 501 does not have to traverse thefull length from septum 221 to threaded chamber 404, it avoids crampingthe fluid flow path. Accordingly, single channel 501 is not made with along, thin pin either.

FIG. 6 is an illustration of exemplary connector 200 assembled and readyfor use, according to one embodiment. Housing 230 may be made ofmaterial including polycarbonate, polystyrene and acrylonitrilebutadiene styrene. Housing 230 includes female luer fitting 231, which,in some embodiments, meets ISO standard 594. Similarly, theconfigurations of the male luer at the distal end of housing 230 andformed with base 210, in some embodiments, meets ISO standard 594. Valveelement 220 is disposed within housing 230 and may be made of elasticmaterial such as silicone rubber, which is deformable and biocompatible.

FIG. 7 is an illustration of exemplary connector 700, adapted accordingto one embodiment. Connector 700 is similar to connector 200 (e.g.,FIGS. 2-6) but uses a slot and key fitting to mate housing 730 to base710, instead of the v-shaped fitting featured in connector 200. In aslot and key configuration, base 710 has a protrusion (key) that issized to fit into a slot in the inner surface of housing 730 (or viseversa). During manufacture, base 710 and valve element 220 are insertedinto housing 730 and turned it until the slot mates with the key. Base710 and housing 730 are then welded. The scope of embodiments is notlimited to a slot and key fitting or a v-shaped fitting, as any of avariety of techniques for mating a base and a housing can be used in avariety of embodiments.

FIG. 8 is an illustration of exemplary method 800 for manufacturing apositive displacement needleless connector according to one embodiment.Method 800 may be performed, for example, by a human and/or one or moremachines.

In block 801, a distal end of the valve element is fastened to aproximal end of the base. The fastening creates a seal between the valveelement and the base separating the septum from a fluid flow pathbetween the first and second luer fittings. Block 801 creates anassembly, such as that shown in FIG. 3A, which includes a valve elementand a base mated together. In one example, the valve element and baseare mated using a snap fitting, though other fastening techniques can beused in other embodiments.

In block 802, the valve element and the base are disposed within thehousing. For instance, a v-shaped fitting can be used, such as thatshown in FIGS. 3A and 3B, that self-aligns the base and housing, thoughother fittings, such as a key and slot and can be used. When the valveand base are disposed within the housing, the proximal end of the valveelement creates one or more seals at the proximal end of the housing.

In block 803, the base and housing are permanently affixed. Varioustechniques can be used in block 803, such as ultrasonic welding,applying adhesives, and the like. In this example, the base and housingfit together tightly so that a seal is created that separates airventing paths from fluid flow paths after the base and housing arepermanently affixed. Various embodiments are not limited to the processshown in FIG. 8, as various actions may be added, omitted, rearranged,or modified.

Some embodiments may enjoy one or more advantages over prior solutions.In one aspect, elimination of the flange of FIGS. 1A and 1B decreasesthe size of the valve element and, in turn, the connector as a whole. Aconnector with a smaller volume is generally expected to have a smallerpriming volume, as well, which may reduce fluid and waste and may bemore visually appealing to health care professionals. Additionally, someembodiments have a reduced overall width, which is generally morecomfortable to a patient when catheter is taped to the skin close to theconnector.

Although the present invention and its advantages have been described indetail, it should be understood that various changes, substitutions andalterations can be made herein without departing from the spirit andscope of the invention as defined by the appended claims. Moreover, thescope of the present application is not intended to be limited to theparticular embodiments of the process, machine, manufacture, compositionof matter, means, methods and steps described in the specification. Asone of ordinary skill in the art will readily appreciate from thedisclosure of the present invention, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized according to the present invention.Accordingly, the appended claims are intended to include within theirscope such processes, machines, manufacture, compositions of matter,means, methods, or steps.

What is claimed is:
 1. A positive-displacement needleless accessconnector comprising: a housing that has a first luer fitting at aproximal end thereof; a base that has a second luer fitting at a distalend thereof; and a valve element with a proximal end that creates a sealat the first luer fitting and fastens to the base so that a surface ofthe valve element is substantially flush with a surface of the base. 2.The positive-displacement needleless access connector of claim 1 inwhich the housing and the base have corresponding, mating surfaces. 3.The positive-displacement needleless access connector of claim 2 inwhich the corresponding, mating surfaces comprise v-shaped cam surfaces.4. The positive-displacement needleless access connector of claim 2 inwhich the corresponding, mating surfaces comprise a slot and keyfitting.
 5. The positive-displacement needleless access connector ofclaim 1 in which the housing, valve element, and base define a fluidflow path from the first luer fitting to the second luer fitting.
 6. Thepositive-displacement needleless access connector of claim 5 in whichthe valve element includes a septum, and the valve element and the basedefine an air passageway that connects the septum with an atmosphere. 7.The positive-displacement needleless access connector of claim 6 inwhich the air passageway is sealed from the fluid flow path.
 8. Thepositive-displacement needleless access connector of claim 1 in whichthe distal end of the valve element fastens to the base using a snappingmechanism.
 9. The positive-displacement needleless access connector ofclaim 1 in which the housing is coupled to the base using a “v”-shapedfitting.
 10. The positive-displacement needleless access connector ofclaim 1 in which the housing is coupled to the base using a key and slotfitting.
 11. The positive-displacement needleless access connector ofclaim 1 comprising a “Y”-shaped vent path from the septum to a distalend of the base.
 12. The positive-displacement needleless accessconnector of claim 1 in which the “Y”-shaped vent path comprisingtriangularly shaped branches.
 13. The positive-displacement needlelessaccess connector of claim 1, wherein the base and the valve elementcouple to each other to create an assembly that has a greatest outerdiameter that is smaller than an inner diameter of the housing.
 14. Thepositive-displacement needleless access connector of claim 1, whereinthe valve element fastens to a proximal end of the base using aninterlocking snap fitting.
 15. The positive-displacement needlelessaccess connector of claim 14 in which an air passageway from a septum ofthe valve element comprises a single path axially disposed within aportion of the base that forms part of the snap fitting.
 16. Thepositive-displacement needleless access connector of claim 15 in whichthe air passageway further comprises branches from the single path tothe atmosphere.
 17. The positive-displacement needleless accessconnector of claim 16 in which the branches are triangularly shaped. 18.A method of assembling a needleless access connector, the needlelessaccess connector including a housing that has a first luer fitting at aproximal end thereof, a base that has a second luer fitting at a distalend thereof, and a valve element with a septum and a proximal end thatcreates a first seal at the first luer fitting, the method comprising:fastening a distal end of the valve element to a proximal end of thebase, creating a second seal between the valve element and the baseseparating the septum from a fluid flow path between the first andsecond luer fittings, wherein outer surfaces of the valve element andthe base are flush where said outer surfaces meet; and disposing thevalve element and the base within the housing.
 19. The method of claim18 in which fastening a distal end of the valve element to a proximalend of the base comprises forcing an interlocking snap fitting together.20. The method of claim 18 further comprising permanently affixing thebase to the housing.